feat(3.6.9): OpenCode Zen + Nous Research (Hermes) providers

Add two new model providers, both usable via API key or --subscription
(local CLI login, no key):

- opencode: OpenCode Zen gateway (OPENCODE_API_KEY, opencode.ai/zen/v1).
  Subscription mode drives the `opencode` CLI (`opencode run --auto`).
  Supports the Playwright MCP (--mcp): our .mcp.json is converted to
  OpenCode's own config schema and injected via OPENCODE_CONFIG.

- nous: Nous Research / Hermes models (NOUS_API_KEY,
  inference-api.nousresearch.com/v1). Subscription mode drives the
  `hermes` CLI (NousResearch/hermes-agent) on the user's Nous Portal
  OAuth login (`hermes setup --portal`), via `hermes chat -q`. No
  CLI-level MCP hook — falls back to Hermes's own built-in toolsets
  (web/terminal/computer-use).

Both wired into cli_binary_for, installed_cli_backends, cli_login_status
(prompt passed as argv, not stdin — neither CLI reads stdin for this).

Bump version 3.6.8 -> 3.6.9 across Cargo.toml, README, TUTORIAL, setup.sh,
install.ps1, and in-binary version strings. README/.env.example updated
with the new provider rows and subscription-login table.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HHFAVCHMvRkTy9Wgw7SayG

install.ps1

@@ -14,7 +14,7 @@ function Ok ($m) { Write-Host "  + $m" -ForegroundColor Green }
 function Warn($m){ Write-Host "  ! $m" -ForegroundColor Yellow }
 
 Write-Host ""
-Write-Host "  NeuroSploit installer (Windows) — v3.6.8" -ForegroundColor Cyan
+Write-Host "  NeuroSploit installer (Windows) — v3.6.9" -ForegroundColor Cyan
 
 # arch → asset arch (only x64 prebuilt today; arm64 falls back to source)
 $rawArch = $env:PROCESSOR_ARCHITECTURE
@@ -29,7 +29,7 @@ $ref  = $env:NEUROSPLOIT_REF
 if (-not $ref) {
   try { $ref = (Invoke-RestMethod "https://api.github.com/repos/$slug/releases/latest").tag_name } catch { }
 }
-if (-not $ref) { $ref = "v3.6.8" }
+if (-not $ref) { $ref = "v3.6.9" }
 Say "Release: $ref"
 
 New-Item -ItemType Directory -Force -Path $dir | Out-Null